Felbamate add-on therapy for drug-resistant focal epilepsy.

BACKGROUND: This is an updated version of the Cochrane Review first published in 2011, and most recently updated in 2019. Epilepsy is a chronic and disabling neurological disorder, affecting approximately 1% of the population. Up to 30% of people with epilepsy have seizures that are resistant to currently available antiepileptic drugs and require treatment with multiple antiepileptic drugs in combination. Felbamate is a second-generation antiepileptic drug that can be used as add-on therapy to standard antiepileptic drugs. OBJECTIVES: To evaluate the efficacy and tolerability of felbamate versus placebo when used as an add-on treatment for people with drug-resistant focal-onset epilepsy. SEARCH METHODS: For the latest update, we searched the Cochrane Register of Studies (CRS Web) and MEDLINE (Ovid, 1946 to 13 July 2021) on 15 July 2021. There were no language or time restrictions. We reviewed the reference lists of retrieved studies to search for additional reports of relevant studies. We also contacted the manufacturers of felbamate and experts in the field for information about any unpublished or ongoing studies. SELECTION CRITERIA: We searched for randomised placebo-controlled add-on studies of people of any age with drug-resistant focal seizures. The studies could be double-blind, single-blind or unblinded and could be of parallel-group or cross-over design. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies for inclusion and extracted information. In the case of disagreements, a third review author arbitrated. Review authors assessed the following outcomes: 50% or greater reduction in seizure frequency; absolute or percentage reduction in seizure frequency; treatment withdrawal; adverse effects; quality of life. MAIN RESULTS: We included four randomised controlled trials, representing a total of 236 participants, in the review. Two trials had parallel-group design, the third had a two-period cross-over design, and the fourth had a three-period cross-over design. We judged all four studies to be at an unclear risk of bias overall. Bias arose from the incomplete reporting of methodological details, the incomplete and selective reporting of outcome data, and from participants having unstable drug regimens during experimental treatment in one trial. Due to significant methodological heterogeneity, clinical heterogeneity and differences in outcome measures, it was not possible to perform a meta-analysis of the extracted data. Only one study reported the outcome of 50% or greater reduction in seizure frequency, whilst three studies reported percentage reduction in seizure frequency compared to placebo. One study claimed an average seizure reduction of 35.8% with add-on felbamate whilst another study claimed a more modest reduction of 4.2%. Both studies reported that seizure frequency increased with add-on placebo and that there was a significant difference in seizure reduction between felbamate and placebo (P = 0.0005 and P = 0.018, respectively). The third study reported a 14% reduction in seizure frequency with add-on felbamate but stated that the difference between treatments was not significant. There were conflicting results regarding treatment withdrawal. One study reported a higher treatment withdrawal for placebo-randomised participants, whereas the other three studies reported higher treatment withdrawal rates for felbamate-randomised participants. Notably, the treatment withdrawal rates for felbamate treatment groups across all four studies remained reasonably low (less than 10%), suggesting that felbamate may be well tolerated. Felbamate-randomised participants most commonly withdrew from treatment due to adverse effects. The adverse effects consistently reported by all four studies were headache, dizziness and nausea. All three adverse effects were reported by 23% to 40% of felbamate-treated participants versus 3% to 15% of placebo-treated participants. We assessed the evidence for all outcomes using GRADE and rated the evidence as very low certainty, meaning that we have little confidence in the findings reported. We mainly downgraded evidence for imprecision due to the narrative synthesis conducted and the low number of events. We stress that the true effect of felbamate could likely be significantly different from that reported in this current review update. AUTHORS' CONCLUSIONS: In view of the methodological deficiencies, the limited number of included studies and the differences in outcome measures, we have found no reliable evidence to support the use of felbamate as an add-on therapy in people with drug-resistant focal-onset epilepsy. A large-scale, randomised controlled trial conducted over a longer period of time is required to inform clinical practice.

Core outcome set development for childhood epilepsy treated with ketogenic diet therapy: Results of a scoping review and parent interviews.

PURPOSE: Clinical trials on childhood epilepsy treated with ketogenic diet (KD) use a wide range of outcomes, however, patients and decision-makers often do not perceive the outcomes used as the most important. We sought parental opinion on outcomes of importance and compared these to outcomes reported in published research. METHODS: Ethical approval (London-Surrey-REC19/LO/1680). A scoping review identified outcomes reported in previous studies of childhood epilepsy and KD. Parents were recruited from nine KD centres (UK), charities and social media (international), then interviewed (Jan-April 2020) to explore priority outcomes. Content analysis identified all outcomes in transcripts. Parent identified outcomes were compared with those in the scoping review. Outcomes were collated and grouped into domains according to the COMET Taxonomy. RESULTS: Of 2663 articles;147 met inclusion criteria. 921 verbatim outcomes were sorted into 90 discrete outcomes, reduced to 70 in consultation with the study advisory group, then classified into 21 domains. Parents (n = 21) identified 39 outcomes as important from the scoping review and seven new outcomes. They prioritised both physiological and functional outcomes in contrast to past studies, which prioritised physiological outcomes. CONCLUSION: Little consistency exists in the outcomes used in childhood epilepsy and KD research. Those traditionally used do not adequately reflect parents' important outcomes for their child. Clinical trials should consider the broader priorities of parents when choosing outcomes, in particular, functional outcomes. Identified outcomes will inform an international two-round Delphi-study with parent, professional and researcher participants to develop a core outcome set for this clinical area (COMET registration #1116).

Carisbamate add-on therapy for drug-resistant focal epilepsy.

BACKGROUND: Epilepsy is one of the most common neurological disorders. Many people with epilepsy are drug-resistant and require add-on therapy, meaning that they concomitantly take multiple antiepileptic drugs. Carisbamate is a drug which is taken orally and inhibits voltage-gated sodium channels. Carisbamate may be useful for drug-resistant focal epilepsy. OBJECTIVES: To evaluate the efficacy and tolerability of carisbamate when used as an add-on therapy for drug-resistant focal epilepsy. SEARCH METHODS: We searched the following databases on 8 April 2021: Cochrane Register of Studies (CRS Web) and MEDLINE (Ovid) 1946 to April 07, 2021. CRS Web includes randomised or quasi-randomised controlled trials from PubMed, Embase, ClinicalTrials.gov, WHO ICTRP, the Cochrane Central Register of Controlled Trials (CENTRAL), and the specialised registers of Cochrane review groups including Epilepsy. We also searched ongoing trials registers, checked reference lists, and contacted authors of the included trials. SELECTION CRITERIA: Double-blind randomised controlled trials (RCTs) comparing carisbamate versus placebo or another antiepileptic drug, as add-on therapy for drug-resistant focal epilepsy. Trials could have a parallel-group or cross-over design. DATA COLLECTION AND ANALYSIS: Two review authors independently selected the trials for inclusion, assessed trial quality, and extracted data. The primary outcome was 50% or greater reduction in seizure frequency (responder rate). The secondary outcomes were: seizure freedom, treatment withdrawal (for any reason and due to adverse events); adverse events, and quality of life. We analysed data using the Mantel-Haenszel statistical method and according to the intention-to-treat population. We presented results as risk ratios (RRs) with 95% confidence intervals (CIs). MAIN RESULTS: We included four RCTs involving a total of 2211 participants. All four trials compared carisbamate with placebo for drug-resistant focal epilepsy. Participants in all trials were over 16 years of age and received at least one other antiepileptic drug concomitantly. We detected substantial risk of bias across the included trials. All four trials were at high risk of attrition bias due to the incomplete reporting of attrition and the high treatment withdrawal rates noted, especially with higher doses. All four trials also had unclear risk of detection bias, as they did not specify whether outcome assessors were blinded. Meta-analysis suggested that carisbamate produced a higher responder rate compared to placebo (RR 1.36, 95% CI 1.14 to 1.62; 4 studies; moderate-certainty evidence). More participants in the carsibamate group achieved seizure freedom (RR 2.43, 95% CI 0.84 to 7.03; 1 study); withdrew from treatment for any reason (RR 1.32, 95% CI 0.82 to 2.12; 4 studies); and withdrew from treatment due to adverse events (RR 1.80, 95% CI 0.78 to 4.17; 4 studies) than in the placebo group. However, the evidence for the three outcomes was very low-certainty. There was no difference between treatment groups for the proportion of participants experiencing at least one adverse event (RR 1.10, 95% CI 0.93 to 1.30; 2 studies; low-certainty evidence). More participants in the carisbamate group than in the placebo group developed dizziness (RR 2.06, 95% CI 1.23 to 3.44; 4 studies; very low-certainty evidence) and somnolence (RR 1.82, 95% CI 1.28 to 2.58; 4 studies; low-certainty evidence), but not fatigue (RR 1.11, 95% CI 0.73 to 1.68; 3 studies); headache (RR 1.13, 95% CI 0.92 to 1.38; 4 studies); or nausea (RR 1.19, 95% CI 0.81 to 1.75; 3 studies). None of the included trials reported quality of life. AUTHORS' CONCLUSIONS: The results suggest that carisbamate may demonstrate efficacy and tolerability as an add-on therapy for drug-resistant focal epilepsy. Importantly, the evidence for all outcomes except responder rate was of low to very low certainty, therefore we are uncertain of the accuracy of the reported effects. The certainty of the evidence is limited by the significant risk of bias associated with the included studies, as well as the statistical heterogeneity detected for some outcomes. Consequently, it is difficult for these findings to inform clinical practice. The studies were all of short duration and only included adult study populations. There is a need for further RCTs with more clear methodology, long-term follow-up, more clinical outcomes, more seizure types, and a broader range of participants.

Keto-on-the-Clock: A Survey of Dietetic Care Contact Time Taken to Provide Ketogenic Diets for Drug-Resistant Epilepsy in the UK.

Medical ketogenic diets (KDs) are effective yet resource-intensive treatment options for drug-resistant epilepsy (DRE). We investigated dietetic care contact time, as no recent data exist. An online survey was circulated to ketogenic dietitians in the UK and Ireland. Data were collected considering feeding route, KD variant and type of ketogenic enteral feed (KEF), and the estimated number of hours spent on patient-related activities during the patient journey. Fifteen dietitians representing nine KD centres responded. Of 335 patients, 267 (80%) were 18 years old or under. Dietitians spent a median of 162 h (IQR 54) of care contact time per patient of which a median of 48% (IQR 6) was direct contact. Most time was required for the classical KD taken orally (median 193 h; IQR 213) as a combined tube and oral intake (median 211 h; IQR 172) or a blended food KEF (median 189 h; IQR 148). Care contact time per month was higher for all KDs during the three-month initial trial compared to the two-year follow-up stage. Patients and caregivers with characteristics such as learning or language difficulties were identified as taking longer. Twelve out of fifteen (80%) respondents managed patients following the KD for more than two years, requiring an estimated median contact care time of 2 h (IQR 2) per patient per month. Ten out of fifteen (67%) reported insufficient official hours for dietetic activities. Our small survey gives insight into estimated dietetic care contact time, with potential application for KD provision and service delivery.

Ketogenic diets for drug-resistant epilepsy.

BACKGROUND: Ketogenic diets (KDs) are high in fat and low in carbohydrates and have been suggested to reduce seizure frequency in people with epilepsy. Such diets may be beneficial for children with drug-resistant epilepsy. This is an update of a review first published in 2003, and last updated in 2018. OBJECTIVES: To assess the effects of ketogenic diets for people with drug-resistant epilepsy. SEARCH METHODS: For this update, we searched the Cochrane Register of Studies (CRS Web) and MEDLINE (Ovid, 1946 to 26 April 2019) on 29 April 2019. The Cochrane Register of Studies includes the Cochrane Epilepsy Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), and randomised controlled trials (RCTs) from Embase, ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We imposed no language restrictions. We checked the reference lists of retrieved studies for additional relevant studies. SELECTION CRITERIA: RCTs or quasi-RCTs of KDs for people of any age with drug-resistant epilepsy. DATA COLLECTION AND ANALYSIS: Two review authors independently applied predefined criteria to extract data and evaluated study quality. We assessed the outcomes: seizure freedom, seizure reduction (50% or greater reduction in seizure frequency), adverse effects, cognition and behaviour, quality of life, and attrition rate. We incorporated a meta-analysis. We utilised an intention-to-treat (ITT) population for all primary analyses. We presented the results as risk ratios (RRs) with 95% confidence intervals (CIs). MAIN RESULTS: We identified 13 studies with 932 participants; 711 children (4 months to 18 years) and 221 adults (16 years and over). We assessed all 13 studies to be at high risk of performance and detection bias, due to lack of blinding. Assessments varied from low to high risk of bias for all other domains. We rated the evidence for all outcomes as low to very low certainty. Ketogenic diets versus usual care for children Seizure freedom (RR 3.16, 95% CI 1.20 to 8.35; P = 0.02; 4 studies, 385 participants; very low-certainty evidence) and seizure reduction (RR 5.80, 95% CI 3.48 to 9.65; P < 0.001; 4 studies, 385 participants; low-certainty evidence) favoured KDs (including: classic KD, medium-chain triglyceride (MCT) KD combined, MCT KD only, simplified modified Atkins diet (MAD) compared to usual care for children. We are not confident that these estimated effects are accurate. The most commonly reported adverse effects were vomiting, constipation and diarrhoea for both the intervention and usual care group, but the true effect could be substantially different (low-certainty evidence). Ketogenic diet versus usual care for adults In adults, no participants experienced seizure freedom. Seizure reduction favoured KDs (MAD only) over usual care but, again, we are not confident that the effect estimated is accurate (RR 5.03, 95% CI 0.26 to 97.68; P = 0.29; 2 studies, 141 participants; very low-certainty evidence). Adults receiving MAD most commonly reported vomiting, constipation and diarrhoea (very low-certainty evidence). One study reported a reduction in body mass index (BMI) plus increased cholesterol in the MAD group. The other reported weight loss. The true effect could be substantially different to that reported. Ketogenic diet versus ketogenic diet for children Up to 55% of children achieved seizure freedom with a classical 4:1 KD after three months whilst up to 85% of children achieved seizure reduction (very low-certainty evidence). One trial reported a greater incidence of seizure reduction with gradual-onset KD, as opposed to fasting-onset KD. Up to 25% of children were seizure free with MAD and up to 60% achieved seizure reduction. Up to 25% of children became seizure free with MAD and up to 60% experienced seizure reduction. One study used a simplified MAD (sMAD) and reported that 15% of children gained seizure freedom rates and 56% achieved seizure reduction. We judged all the evidence described as very low certainty, thus we are very unsure whether the results are accurate. The most commonly reported adverse effects were vomiting, constipation and diarrhoea (5 studies, very low-certainty evidence). Two studies reported weight loss. One stated that weight loss and gastrointestinal disturbances were more frequent, with 4:1 versus 3:1 KD, whilst one reported no difference in weight loss with 20 mg/d versus 10 mg/d carbohydrates. In one study, there was a higher incidence of hypercalcuria amongst children receiving classic KD compared to MAD. All effects described are unlikely to be accurate. Ketogenic diet versus ketogenic diet for adults One study randomised 80 adults (aged 18 years and over) to either MAD plus KetoCal during the first month with MAD alone for the second month, or MAD alone for the first month followed by MAD plus KetoCal for the second month. No adults achieved seizure freedom. More adults achieved seizure reduction at one month with MAD alone (42.5%) compared to MAD plus KetoCal (32.5%), however, by three months only 10% of adults in both groups maintained seizure reduction. The evidence for both outcomes was of very low certainty; we are very uncertain whether the effects are accurate. Constipation was more frequently reported in the MAD plus KetoCal group (17.5%) compared to the MAD only group (5%) (1 study, very low-certainty evidence). Diarrhoea and increase/change in seizure pattern/semiology were also commonly reported (17.5% to 20% of participants). The true effects of the diets could be substantially different to that reported. AUTHORS' CONCLUSIONS: The evidence suggests that KDs could demonstrate effectiveness in children with drug-resistant epilepsy, however, the evidence for the use of KDs in adults remains uncertain. We identified a limited number of studies which all had small sample sizes. Due to the associated risk of bias and imprecision caused by small study populations, the evidence for the use of KDs was of low to very low certainty. More palatable but related diets, such as the MAD, may have a similar effect on seizure control as the classical KD, but could be associated with fewer adverse effects. This assumption requires more investigation. For people who have drug-resistant epilepsy or who are unsuitable for surgical intervention, KDs remain a valid option. Further research is required, particularly for adults with drug-resistant epilepsy.

Biochemical assessment of patients following ketogenic diets for epilepsy: Current practice in the UK and Ireland.

OBJECTIVE: Biochemical assessment is recommended for patients prior to initiating and following a ketogenic diet (KD). There is no published literature regarding current practice in the UK and Ireland. We aimed to explore practice in comparison with international guidelines, determine approximate costs of biochemical testing in KD patients across the UK and Ireland, and promote greater consistency in KD services nationally. METHODS: A survey was designed to determine the biochemical tests requested for patients at baseline, 3, 6, 12, 18, and 24 months + on KD. The survey was circulated to 39 centers across the UK and Ireland. RESULTS: Sixteen centers completed the survey. Full blood count, electrolytes, calcium, liver function tests (LFTs), lipid profile, and vitamin D were requested at all centers at baseline, in keeping with international guidelines. Bicarbonate, total protein, and urinalysis were less consistently requested. Magnesium and zinc were requested by all centers, despite not being specifically recommended for pre-diet evaluation in guidelines. Urea and electrolyte profiles and some LFTs were consistently requested at follow-up, in accordance with guidelines. Other LFTs and renal tests, full blood count, lipid profile, acylcarnitine profile, selenium, vitamin D, and urinalysis were less consistently requested at follow-up. The mean costs of the lowest and highest number of tests requested at baseline in our participating centers were £167.54 and £501.93; the mean costs of the lowest and highest number of tests requested at 3-month follow-up were £19.17 and £450.06. SIGNIFICANCE: Biochemical monitoring of KD patients varies widely across the UK and Ireland and does not fully correspond to international best practice guidelines. With an ongoing drive for cost-effectiveness within health care, further work is needed to streamline practice while ensuring patient safety.

Ketogenic diets as an adjuvant therapy for glioblastoma (KEATING): a randomized, mixed methods, feasibility study.

PURPOSE: We conducted a feasibility study to investigate the use of ketogenic diets (KDs) as an adjuvant therapy for patients with glioblastoma (GBM), investigating (i) trial feasibility; (ii) potential impacts of the trial on patients' quality of life and health; (iii) patients' perspectives of their decision-making when invited to participate in the trial and (iv) recommending improvements to optimize future phase III trials. METHODS: A single-center, prospective, randomized, pilot study (KEATING), with an embedded qualitative design. Twelve newly diagnosed patients with GBM were randomized 1:1 to modified ketogenic diet (MKD) or medium chain triglyceride ketogenic diet (MCTKD). Primary outcome was retention at three months. Semi-structured interviews were conducted with a purposive sample of patients and caregivers (n = 15). Descriptive statistics were used for quantitative outcomes and qualitative data were analyzed thematically aided by NVivo. RESULTS: KEATING achieved recruitment targets, but the recruitment rate was low (28.6%). Retention was poor; only four of 12 patients completed the three-month diet (MCTKD n = 3; MKD n = 1). Participants' decisions were intuitive and emotional; caregivers supported diet implementation and influenced the patients' decision to participate. Those who declined made a deliberative and considered decision factoring diet burden and quality of life. A three-month diet was undesirable to patients who declined and withdrew. CONCLUSION: Recruitment to a KD trial for patients with GBM is possible. A six-week intervention period is proposed for a phase III trial. The role of caregivers should not be underestimated. Future trials should optimize and adequately support the decision-making of patients.

Clobazam add-on therapy for drug-resistant epilepsy.

BACKGROUND: Epilepsy affects approximately 1% of the population, with up to 30% of patients continuing to have seizures, despite antiepileptic drug treatment. Clobazam is a 1,5-benzodiazepine and is commonly used as an add-on treatment for drug-resistant epilepsy. This review is an updated version of the original Cochrane Review, first published in 2008, and examines the most current literature regarding clobazam as an add-on for drug-resistant epilepsy. OBJECTIVES: To assess the efficacy, effectiveness and tolerability of clobazam as an add-on therapy for drug-resistant generalised-onset and focal-onset seizures, with or without secondary generalisation, in adults and children. SEARCH METHODS: For the latest update, we searched the following databases on 9 October 2018: Cochrane Register of Studies (CRS Web), which includes the Cochrane Epilepsy Group Specialized Register and the Cochrane Central Register of Controlled Trials (CENTRAL), Medline (Ovid) 1946 to 8 October, 2018, ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform (ICTRP). For some previous updates we also searched SCOPUS, DARE, and BIOSIS Previews, but these are no longer needed. (SCOPUS was searched as a substitute for EMBASE, but randomised and quasi-randomised controlled trials in EMBASE are now included in CENTRAL; DARE ceased operation at the end of March 2015; BIOSIS Previews yielded no relevant items that were not found in the other databases). SELECTION CRITERIA: Randomised trials of add-on clobazam, with adequate methods of allocation concealment, recruiting patients with drug-resistant focal or generalised-onset seizures, with a minimum treatment period of eight weeks. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion and extracted relevant data. The following outcomes were assessed: 50% or greater reduction in seizures, seizure freedom, treatment withdrawal and adverse events. MAIN RESULTS: Four double-blind, placebo-controlled, cross-over studies, representing 197 participants, were included in the review. All four studies were assessed as having unclear risk of bias due to the unavailability of methodological details. The studies demonstrated significant methodological heterogeneity and differences in outcome measures were noted. Consequently, it was not possible to summarise the data in a meta-analysis. Instead, findings were summarised in a narrative data synthesis, Only two of the studies reported 50% or greater seizure reduction. They respectively reported that 57.7% and 52.4% of participants receiving add-on clobazam experienced a 50% or greater reduction in seizure frequency, although publication bias needs to be considered (2 RCTs, n = 47, very low-quality evidence). Seizure freedom was reported by three of the included studies. Collectively, 27 out of 175 patients were seizure-free during treatment with clobazam (3 RCTs, n = 175, very low-quality evidence). Two studies specifically stated that seizure freedom was not observed in any of the participants receiving add-on placebo. Treatment withdrawal was reported by all four studies. There was a slightly higher incidence of treatment withdrawal associated with receiving clobazam, although the overall incidence was still fairly low (4 RCTs, n = 197, very low-quality evidence). Adverse events were only described in two of the studies, reportedly 36% and 85% of participants experienced one or more adverse events whilst receiving clobazam. The most commonly reported adverse event was drowsiness. AUTHORS' CONCLUSIONS: Clobazam as an add-on treatment may reduce seizure frequency and may be most effective in focal-onset seizures. It is important to recognise that this finding has been derived from very low-quality evidence and from studies judged to have an unclear risk of bias. It remains unclear which population demographic will best benefit from clobazam and over what time-frame. A large-scale, randomised controlled trial, conducted over a greater period of time, incorporating subgroups with differing seizure types, is required to effectively inform clinical practice.

Tiagabine add-on therapy for drug-resistant focal epilepsy.

BACKGROUND: Epilepsy is a common neurological condition that affects up to 1% of the population. Nearly 30% of people with epilepsy are resistant to currently available antiepileptic drugs (AEDs) and require treatment with multiple antiepileptic drugs in combination. Tiagabine is one of the newer AEDs that can be used as an adjunct (add-on) to standard AEDs. OBJECTIVES: To evaluate the efficacy and tolerability of tiagabine when used as an add-on treatment for people with drug-resistant focal seizures. SEARCH METHODS: This is an updated Cochrane review, last published in 2014. For the latest update, we searched the following databases on 22 January 2019: Cochrane Register of Studies (CRS Web), which includes the Cochrane Epilepsy Group's Specialized Register and the Cochrane Central Register of Controlled Trials, MEDLINE (Ovid, 1946 to January 21, 2019), ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform. We imposed no language restrictions. We also contacted the manufacturers of tiagabine and experts in the field to identify any ongoing or unpublished studies. SELECTION CRITERIA: We included randomised placebo-controlled add-on trials conducted in people of any age with focal epilepsy. The studies could be double-, single-, or unblinded and of parallel or cross-over design. They had to have a minimum treatment period of eight weeks. We also included trials using an active drug control group. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and extracted data according to the standard methodological procedures expected by the Cochrane Collaboration for this review update. We resolved disagreements by discussion. Outcomes investigated included 50% or greater reduction in seizure frequency, treatment withdrawal, adverse effects, effects on cognition and quality of life. The primary analyses were performed by intention-to-treat. We calculated worst-case and best-case analyses for seizure outcomes. We evaluated dose response using regression models. Two review authors assessed risk of bias in each study using the Cochrane 'Risk of bias' tool. MAIN RESULTS: No further studies were added since the previous update in 2014. The review included six trials (four parallel-group and two cross-over group trials) consisting of 948 participants. For the main comparison, tiagabine versus placebo, all participants were aged between 12 and 77 years and the study treatment periods ranged from 12 to 22 weeks. The overall risk ratio (RR) with 95% confidence intervals (CIs) for a 50% or greater reduction in seizure frequency (tiagabine versus placebo) was 3.16 (95% CI 1.97 to 5.07; 3 trials; 769 participants; high-certainty evidence). Because of differences in response rates among trials, regression models were unable to provide reliable estimates of response to individual doses. The RR for treatment withdrawal (tiagabine versus placebo) was 1.81 (95% CI 1.25 to 2.62; 3 trials, 769 participants; moderate-certainty evidence). Dizziness and tremor were significantly associated with tiagabine therapy. For cognitive and quality-of-life outcomes, the limited available data suggested no significant effects on cognition, mood, or adjustment. One trial comparing tiagabine with an active drug control group (tiagabine versus topiramate) found no significant differences between the two add-on drugs for a 50% or greater reduction in seizure frequency (RR 0.54, 95% CI 0.19 to 1.58; 1 trial; 41 participants) or for treatment withdrawal (RR 1.43, 95% CI 0.74 to 2.74; one trial; 41 participants). We judged two of the six included studies to have low risk of bias, three studies to have an unclear risk of bias, and one study to have a high risk of bias. Methods for randomisation sequence generation were the least reported trial design factor and generated the most concerns regarding risk of bias. We rated the overall certainty of the evidence as largely moderate to high using the GRADE approach. We rated the evidence for two of the adverse effect outcomes, nausea and tremor, as low certainty. AUTHORS' CONCLUSIONS: Tiagabine reduced seizure frequency but was associated with some adverse effects when used as an add-on treatment in people with drug-resistant focal epilepsy. The findings of the current review are mainly applicable to adults and adolescents, and may not necessarily be applicable to children as none of the trials included participants aged under 12 years. We found no significant differences between tiagabine and topiramate as add-on drugs; however, evidence was provided by a single trial and was therefore limited.

Sulthiame add-on therapy for epilepsy.

BACKGROUND: This is an updated version of the Cochrane Review previously published in the Cochrane Database of Systematic Reviews 2015, Issue 10. Epilepsy is a common neurological condition, characterised by recurrent seizures. Most people respond to conventional antiepileptic drugs, however, around 30% will continue to experience seizures, despite treatment with multiple antiepileptic drugs. Sulthiame, also known as sultiame, is a widely used antiepileptic drug in Europe and Israel. We present a summary of the evidence for the use of sulthiame as add-on therapy in epilepsy. OBJECTIVES: To assess the efficacy and tolerability of sulthiame as add-on therapy for people with epilepsy of any aetiology compared with placebo or another antiepileptic drug. SEARCH METHODS: For the latest update, we searched the Cochrane Register of Studies (CRS Web), which includes the Cochrane Epilepsy Group's Specialized Register and CENTRAL (17 January 2019), MEDLINE Ovid (1946 to January 16, 2019), ClinicalTrials.gov and the WHO ICTRP Search Portal (17 January 2019). We imposed no language restrictions. We contacted the manufacturers of sulthiame, and researchers in the field to seek any ongoing or unpublished studies. SELECTION CRITERIA: Randomised controlled trials of add-on sulthiame, with any level of blinding (single, double or unblinded) in people of any age, with epilepsy of any aetiology. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion, and extracted relevant data. We assessed these outcomes: (1) 50% or greater reduction in seizure frequency between baseline and end of follow-up; (2) complete cessation of seizures during follow-up; (3) mean seizure frequency; (4) time-to-treatment withdrawal; (5) adverse effects; and (6) quality of life. We used intention-to-treat for primary analyses. We presented results as risk ratios (RR) with 95% confidence intervals (CIs). However, due to the paucity of trials, we mainly conducted a narrative analysis. MAIN RESULTS: We included one placebo-controlled trial that recruited 37 infants with newly diagnosed West syndrome. This trial was funded by DESITIN Pharma, Germany. During the study, sulthiame was given as an add-on therapy to pyridoxine. No data were reported for the outcomes: 50% or greater reduction in seizure frequency between baseline and end of follow-up; mean seizure frequency; or quality of life. For complete cessation of seizures during a nine-day follow-up period for add-on sulthiame versus placebo, the RR was 11.14 (95% CI 0.67 to 184.47; very low-certainty evidence), however, this difference was not shown to be statistically significant (P = 0.09). The number of infants experiencing one or more adverse events was not significantly different between the two treatment groups (RR 0.85, 95% CI 0.44 to 1.64; very low-certainty evidence; P = 0.63). Somnolence was more prevalent amongst infants randomised to add-on sulthiame compared to placebo, but again, the difference was not statistically significant (RR 3.40, 95% CI 0.42 to 27.59; very low-certainty evidence; P = 0.25). We were unable to conduct meaningful analysis of time-to-treatment withdrawal and adverse effects due to incomplete data. AUTHORS' CONCLUSIONS: Sulthiame may lead to a cessation of seizures when used as an add-on therapy to pyridoxine in infants with West syndrome, however, we are very uncertain about the reliability of this finding. The included study was small and had a significant risk of bias, largely due to the lack of details regarding blinding and the incomplete reporting of outcomes. Both issues negatively impacted the certainty of the evidence. No conclusions can be drawn about the occurrence of adverse effects, change in quality of life, or mean reduction in seizure frequency. No evidence exists for the use of sulthiame as an add-on therapy in people with epilepsy outside West syndrome.Large, multi-centre randomised controlled trials are needed to inform clinical practice, if sulthiame is to be used as an add-on therapy for epilepsy.

Felbamate add-on therapy for drug-resistant focal epilepsy.

BACKGROUND: This is an updated version of the Cochrane Review previously published in 2017.Epilepsy is a chronic and disabling neurological disorder, affecting approximately 1% of the population. Up to 30% of people with epilepsy have seizures that are resistant to currently available antiepileptic drugs and require treatment with multiple antiepileptic drugs in combination. Felbamate is a second-generation antiepileptic drug that can be used as add-on therapy to standard antiepileptic drugs. OBJECTIVES: To evaluate the efficacy and tolerability of felbamate versus placebo when used as an add-on treatment for people with drug-resistant focal-onset epilepsy. SEARCH METHODS: For the latest update we searched the Cochrane Register of Studies (CRS Web), MEDLINE, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP), on 18 December 2018. There were no language or time restrictions. We reviewed the reference lists of retrieved studies to search for additional reports of relevant studies. We also contacted the manufacturers of felbamate and experts in the field for information about any unpublished or ongoing studies. SELECTION CRITERIA: We searched for randomised placebo-controlled add-on studies of people of any age with drug-resistant focal seizures. The studies could be double-blind, single-blind or unblinded and could be of parallel-group or cross-over design. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies for inclusion and extracted information. In the case of disagreements, the third review author arbitrated. Review authors assessed the following outcomes: 50% or greater reduction in seizure frequency; absolute or percentage reduction in seizure frequency; treatment withdrawal; adverse effects; quality of life. MAIN RESULTS: We included four randomised controlled trials, representing a total of 236 participants, in the review. Two trials had parallel-group design, the third had a two-period cross-over design, and the fourth had a three-period cross-over design. We judged all four studies to be at an unclear risk of bias overall. Bias arose from the incomplete reporting of methodological details, the incomplete and selective reporting of outcome data, and from participants having unstable drug regimens during experimental treatment in one trial. Due to significant methodological heterogeneity, clinical heterogeneity and differences in outcome measures, it was not possible to perform a meta-analysis of the extracted data.Only one study reported the outcome, 50% or greater reduction in seizure frequency, whilst three studies reported percentage reduction in seizure frequency compared to placebo. One study claimed an average seizure reduction of 35.8% with add-on felbamate while another study claimed a more modest reduction of 4.2%. Both studies reported that seizure frequency increased with add-on placebo and that there was a significant difference in seizure reduction between felbamate and placebo (P = 0.0005 and P = 0.018, respectively). The third study reported a 14% reduction in seizure frequency with add-on felbamate but stated that the difference between treatments was not significant. There were conflicting results regarding treatment withdrawal. One study reported a higher treatment withdrawal for placebo-randomised participants, whereas the other three studies reported higher treatment withdrawal rates for felbamate-randomised participants. Notably, the treatment withdrawal rates for felbamate treatment groups across all four studies remained reasonably low (less than 10%), suggesting that felbamate may be well tolerated. Felbamate-randomised participants most commonly withdrew from treatment due to adverse effects. The adverse effects consistently reported by all four studies were: headache, dizziness and nausea. All three adverse effects were reported by 23% to 40% of felbamate-treated participants versus 3% to 15% of placebo-treated participants.We assessed the evidence for all outcomes using GRADE and found it as being very-low certainty, meaning that we have little confidence in the findings reported. We mainly downgraded evidence for imprecision due to the narrative synthesis conducted and the low number of events. We stress that the true effect of felbamate could likely be significantly different from that reported in this current review update. AUTHORS' CONCLUSIONS: In view of the methodological deficiencies, the limited number of included studies and the differences in outcome measures, we have found no reliable evidence to support the use of felbamate as an add-on therapy in people with drug-resistant focal-onset epilepsy. A large-scale, randomised controlled trial conducted over a longer period of time is required to inform clinical practice.

Ketogenic diets for drug-resistant epilepsy.

BACKGROUND: Ketogenic diets (KDs), being high in fat and low in carbohydrates, have been suggested to reduce seizure frequency in people with epilepsy. At present, such diets are mainly recommended for children who continue to have seizures despite treatment with antiepileptic drugs (AEDs) (drug-resistant epilepsy). Recently, there has been interest in less restrictive KDs, including the modified Atkins diet (MAD), and the use of these diets has extended into adult practice. This is an update of a review first published in 2003 and last updated in 2016. OBJECTIVES: To assess the effects of KDs for drug-resistant epilepsy by reviewing the evidence from randomised controlled trials. SEARCH METHODS: For the latest update we searched the Cochrane Epilepsy Group's Specialized Register (11 April 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (CRSO, 11 April 2017), MEDLINE (Ovid, 11 April 2017), ClinicalTrials.gov (11 April 2017) and the WHO International Clinical Trials Registry Platform (ICTRP, 11 April 2017). We imposed no language restrictions. We checked the reference lists of retrieved studies for additional reports of relevant studies. SELECTION CRITERIA: Randomised controlled trials or quasi-randomised controlled trials of ketogenic diets for people with drug-resistant epilepsy. DATA COLLECTION AND ANALYSIS: Two review authors independently applied predefined criteria to extract data and assessed study quality. MAIN RESULTS: We identified 11 randomised controlled trials (RCTs) that generated 15 publications.All trials applied an intention-to-treat analysis with varied randomisation methods. The 11 studies recruited 778 patients; 712 children and adolescents and 66 adults. We assessed all 11 studies to be at low to unclear risk of bias for the following domains: random sequence generation, allocation concealment and selective reporting. For the other domains (blinding, incomplete outcome data, other bias) assessments were varied (low, unclear and high risk of bias). We could not conduct a meta-analysis due to the heterogeneity of the studies and the quality of the evidence was low to very low (GRADE ratings).Reported rates of seizure freedom reached as high as 55% in a classical 4:1 KD group after three months and reported rates of seizure reduction reached as high as 85% in a classical 4:1 KD group after three months (GRADE rating low).One trial found no significant difference between the fasting-onset and gradual-onset KD for rates of seizure freedom, and reported a greater rate of seizure reduction in the gradual-onset KD group.Studies assessing the efficacy of the MAD reported seizure freedom rates of up to 25% and seizure reduction rates of up to 60% in children. One study used a simplified MAD (sMAD) and reported seizure freedom rates of 15% and seizure reduction rates of 56% in children. One study utilised a MAD in adults and reported seizure reduction rates of 35%, but no patients became seizure free (GRADE rating low).Adverse effects of the dietary interventions were experienced in all studies. The most commonly reported adverse effects were gastrointestinal syndromes. It was common that adverse effects were the reason for participants dropping out of trials (GRADE rating low). Other reasons for dropout included lack of efficacy and non-acceptance of the diet (GRADE rating low).Although there was some evidence for greater antiepileptic efficacy for a classical 4:1 KD over lower ratios, the classical 4:1 KD was consistently associated with more adverse effects.One study assessed the effect of dietary interventions on quality of life, cognition and behavioural functioning, reporting participants in the KD group to be more active, more productive and less anxious after four months, compared to the control group. However, no significant difference was found in quality-adjusted life years (QALYs) between the KD group and control group at four or 16 months (GRADE rating very low). AUTHORS' CONCLUSIONS: The RCTs discussed in this review show promising results for the use of KDs in epilepsy. However, the limited number of studies, small sample sizes and the limited studies in adults, resulted in a low to very low overall quality of evidence.There were adverse effects within all of the studies and for all KD variations, such as short-term gastrointestinal-related disturbances and increased cholesterol. However, study periods were short, therefore the long-term risks associated with these adverse effects is unknown. Attrition rates remained a problem with all KDs and across all studies; reasons for this being lack of observed efficacy and dietary tolerance.Only one study reported the use of KDs in adults with epilepsy; therefore further research would be of benefit.Other more palatable but related diets, such as the MAD, may have a similar effect on seizure control as the classical KD, but this assumption requires more investigation. For people who have medically intractable epilepsy or people who are not suitable for surgical intervention, KDs remain a valid option; however, further research is required.

The Modified Ketogenic Diet in Adults with Glioblastoma: An Evaluation of Feasibility and Deliverability within the National Health Service.

There is an increasing interest in the use of the ketogenic diet (KD) as an adjuvant therapy for glioma patients. We assessed the tolerability and feasibility of a modified ketogenic diet (MKD) in patients with glioma, along with willingness of patients to participate in future randomized controlled trials. The study was undertaken in two parts; a patient questionnaire and evaluation of the diet. One hundred and seventy-two questionnaires were completed; 69% (n = 119) of the population reported MKD should be offered to patients with glioma and 73% (n = 125) would be willing to try MKD for 3 months. Six male patients with high grade gliomas tried the diet; 4 completed the 3-month feasibility period. Ketosis was achieved in all patients. The only gastrointestinal side effect was constipation (n = 2). Minimal changes were observed in weight, body mass index, fat mass and cholesterol profiles. MKD was well tolerated, with few side effects and is deliverable within a financially viable, NHS service. There is a high level of interest in the diet within the glioma patient community to ensure adequate recruitment for a clinical trial. Further studies are required to demonstrate efficacy and patient benefit before implementing a service.

The role of ketogenic diets in the therapeutic management of adult and paediatric gliomas: a systematic review.

AIM: We performed a systematic review of the evidence for effectiveness and acceptability of different ketogenic diets (KDs) in the therapeutic management of gliomas. METHODS: The search strategy included searches of seven electronic databases. Data extraction and quality assessment were undertaken independently by two authors. RESULTS: No randomized clinical trials were identified. Six studies (n = 39) met the eligibility criteria for this review - all were case series or reports and therefore at high risk of bias. All studies reported overall or progression-free survival; however the effectiveness of KD interventions could not be established. Dietary acceptability was not reported. CONCLUSION: The effectiveness and acceptability of KDs in the management of gliomas is unknown and high quality randomized controlled trials are needed.

Ketogenic diets as an adjuvant therapy in glioblastoma (the KEATING trial): study protocol for a randomised pilot study.

BACKGROUND: Glioblastoma is the commonest form of malignant brain tumour in adults, affecting 2-3 people per 100,000 per year. Despite current treatment options including surgical resection, radiotherapy and temozolomide chemotherapy, overall survival at 2 years is approximately 27%, with a median survival of 12-14 months. The ketogenic diet (KD) is postulated to work by simulating the metabolic response to fasting by promoting the utilisation of ketones as a primary energy source, and depriving the glycolytic pathways utilised by malignant glioma cells for growth. At present, there is no consensus as to which KD is preferable, with previous case series using different KDs, at different points in the treatment pathway. The aim of this randomised pilot study is to investigate protocol feasibility, tolerability and the impact on patient health and quality of life of two different KDs within an NHS setting. The results of this pilot study will inform which KD will be most deliverable and adhered to by patients in order to test for effectiveness in future trials. METHODS: A prospective, non-blinded, randomised, pilot study will be undertaken in 12 patients with newly diagnosed glioblastoma treated by surgical resection. Patients will be randomised in a ratio of 1:1, using a permuted block randomisation method to one of two diets; the modified ketogenic diet and the medium chain triglyceride ketogenic diet. Primary data collection will take place 12 weeks after starting the diet and secondary data collection after 12 months. Feasibility will be assessed by retention and recruitment rates, ability to enrol patients prior to starting chemoradiotherapy, dietary compliance and adjustments, ketone levels, glucose levels and intervention time. Patient impact will be assessed through quality of life and food acceptability questionnaires, gastrointestinal side effects and changes to biochemical markers and anthropometric measures, assessed at regular intervals. DISCUSSION: The results of this pilot study will be used to inform the feasibility, methodological design and power calculations of future phase III clinical trials investigating the effectiveness of KD as an adjuvant therapy in the management of glioblastoma. TRIAL REGISTRATION: ISRCTN71665562 and NCT03075514.

The modified ketogenic diet for adults with refractory epilepsy: An evaluation of a set up service.

PURPOSE: The ketogenic diet (KD) has been proven to be effective in children with refractory epilepsy and is recommended by the National Institute of Health and Care Excellence (NICE). There is no randomised control trial (RCT) evidence for the clinical or cost effectiveness of KD in adults, for whom the KD is not currently recommended. We assessed the feasibility of the modified ketogenic diet (MKD) in adults with refractory epilepsy along with the willingness of patients to participate in a future RCT. METHODS: The service evaluation was undertaken in two parts; questionnaire and diet evaluation. RESULTS: 102 patients completed a questionnaire, of which 51 patients were willing to try the MKD for 3 months to assess effect on seizures. Forty three patients were willing to participate in a clinical trial to investigate deliverability, efficacy and tolerability. Thirty seven of which would still be willing to participate if the trial were randomised. Of the 17 patients who commenced the diet, 9 completed the 12 week period, 7 of which stayed on the diet for the longer term. Constipation (n=6) and loose stools (n=3) were the only reported adverse effects. CONCLUSION: Our results indicate that there is demand for a ketogenic diet service in adults. The MKD is well tolerated, feasible and financially viable to deliver to adults with epilepsy in the NHS. There is also interest in and willingness to participate in a UK based RCT that would ultimately inform decisions about commissioning appropriate services.